Sheet media imaging systems include laser imaging systems which produce medical images on photosensitive, sheet film from digital medical images generated by diagnostic imaging systems (MRI, CT, US, PET), computed radiography systems, medical image digitizers, digital or analog medical image archives, direct digital radiography or the like. The sheet film can be packaged in optically opaque packaging which is removed under dark room conditions and loaded into a film supply of a laser imager. Dark room film loading is eliminated by the resealable film cartridge disclosed in U.S. Pat. No. 5,473,400, issued Dec. 5, 1995, inventors Lemberger et al. The disclosed cartridge allows for daylight loading and can be reused and removed from the laser imager. U.S. Pat. No. 5,229,585, issued Jul. 20, 1993, inventors Lemberger et al., discloses a bar code system which uses this resealable cartridge to control a laser imaging system. The cartridge has attached to it an optical bar code with a unique cartridge ID, film size, film type information and film sensitometric information. The laser imager has a bar code scanner which reads information from the bar code as the cartridge is opened. An imager management system controls the laser imager as a function of the input data and the information read from the bar code. A film processor develops the film as a function of film type information read from the bar code. The laser imager stores information relating to film usage of the cartridge.
Although the optical bar code system disclosed in the latter two patents is useful for the purposes for which they were intended, certain limitations are inherent in this technology as follows.
1. The optical bar code has a limited data storage capability.
2. There are a limited number of unique bar codes.
3. The data is fixed and cannot be changed.
4. The bar code must be located on the outside of the cartridge to allow scanning, exposing the bar code to wear and dirt which result in bar code read failures.
5. Film usage information is stored in the image management system of the laser imaging system.
Other technologies for encoding data on a cartridge are also limited. Thus, magnetic encodement allows data to be changed but requires precise contact between a magnetic layer on the cartridge and a magnetic head. Electrical contact with a memory chip mounted on a cartridge also requires precise positioning of the cartridge relative to the read/write device. Both technologies are complex and expensive and are susceptible to wear and degradation.
U.S. Pat. No. 5,428,659, issued Jun. 27, 1995, inventors Renner et al. discloses a device for transferring electrical signals and electric energy to the memory device of a cassette by radio frequency signals by means of a capacitive coupling device. Although the disclosed device is useful for the purpose for which it was intended, it requires precise positioning of the cassette for transfer of data and direct contact between the cartridge and the cartridge receiver.
Reference is made to U.S. Pat. No. 6,710,891, (U.S. Ser. No. 09/664,498) filed on Sep. 18, 2000 entitled SHEET MEDIA SYSTEM et al.; U.S. Patent No. 6,173,119 filed on August 11, 1999, entitled CAMERA HAVING RADIO-FREQUENCY IDENTIFICATION TRANSPONDER, by Manico et al.; U.S. Pat. No. 6,381,416 filed on Aug. 11, 1999, titled FILM UNIT HAVING RADIO-FREQUENCY IDENTIFICATION TRAN PONDER, by Manico et al.; U.S. Pat. No. 6,628,316 filed on Dec. 22, 1 98, entitled PRINTER WITH DONOR AND RECEIVER MEDIA SUPPLY TRAYS EACH ADAPTED TO ALLOW A PRINTER TO SENSE TYPE OF MED THEREIN, AND METHOD OF ASSEMBLING THE PRINTER AND TRAYS by Spurr et al.; and U.S. Pat. No. 6,634,814 filed on Aug. 12, 1998, entitled PRINTER MEDIA SUPPLY SPOOL ADAPTED TO ALLOW THE PRINTER TO SENSE TYPE OF MEDIA, AND METHOD OF ASSEMBLING SAME, by purr et al., all of which are commonly assigned and incorporated herein by reference. Reference is also made to U.S. Pat. No. 5,229,585 (Lemberger), U S. Pat. No. 5,428,659 (Renner), and U.S. Pat. No. 5,971,281 (Frary).
There is thus a need for a sheet media system which uses sheet media packaging having encoded data which has a large data storage, which allows reading of and writing to the data storage, which is resistant to degradation due to dirt, wear and tear, and which is simple and economical to implement.